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Study Designs and Research Methods

Introduction

To provide students with the knowledge of study design and the skills required for a variety of data collection methods, including methods of sampling.

Study SessionsStudy Session 1: Formulating Research Aims and ObjectivesStudy Session 2: Introduction to Study designsStudy Session 3: Research methods in Public Health research

SOPH, UWC, Master of Public Health - Public Health Research- Unit 379

UNIT 3

Unit 3 – Session 1Formulating Research Aims and Objective

Introduction

In the previous study session you learnt how to write a literature review. This study session will now take you through the next step of developing your research protocol which is to formulate some research aims and objectives. The aim of this study session is to illustrate the transition from research questions into concrete activities, to guide research activities.

Session Contents1 Learning outcomes of this session2 Readings3 Identify good aims and objectives4 Formulate clear aims and objectives5 Session summary

Timing

This session contains nine tasks aimed at assisting you in developing your confidence in formulating aims and objectives. Follow them through systematically, and you should have the next section of your assignment completed. The timing will depend on your prior experience and work to date.


1 LEARNING OUTCOMES OF THIS SESSION

By the end of this session, you should be better able to meet these intended learning outcomes:

Distinguish between research aims and objectives. List key features of aims and objectives. Evaluate aims and objectives. Write clear aims and objectives.

2 READING

Joubert, G. & Erhlich, R.(2007). Ch 6 - Setting Objectives for Research. In Epidemiology: A Research Manual for South Africa. Cape Town: Oxford University Press: 56 - 63.

3 IDENTIFY GOOD AIMS AND OBJECTIVES

In previous study sessions, you prioritised and analysed a research problem until you focused on a specific aspect of the core problem. You then drew up a problem statement. The literature review assisted you to further clarify the issues and may have given you some ideas about how to address the problem. You are now ready to formulate the overall aim and specific objectives of the research. This section guides you in doing this.

READINGJoubert, G. & Ehrlich, R. (2007). Ch 6 - Setting Objectives for Research. In Epidemiology: A Research Manual for South Africa. Cape Town: Oxford University Press: 56 - 63.

TASK 1 – Compare and summarise features of aims and objectivesRead Joubert and Ehrlich (2007). It describes stages 1 - 3 of writing a research protocol, i.e. stating the research problem, literature review and setting aims and objectives. Answer these questions.

a) What are the main features of a good aim?


b) What are the main features of a good objective?

c) What is the difference between aims and objectives, and how are they related?

d) How do objectives relate to the research methods used?

e) Why is it important to formulate good aims and objectives?

FEEDBACKAccording to Joubert and Ehrlich, a good aim:

is related to the initial research problem. is clear and precise. can be defined. is achievable with the time and resources available.

Good objectives: cover the different aspects or individual components of the problem

and its contributing factors in a coherent way and in a logical sequence.

are clearly phrased in operational terms and are easy to apply in practice.

are commonly phrased in measurable terms. are clear, specific and unambiguous.

The aim of the study states what is expected to be achieved by the study overall, while objectives indicate the specific information the study must yield and the detailed research questions that must be answered to fulfil the aim.

Objectives specify what you will do in your study, where and for what purpose. Objectives indicate what is to be achieved. The methods specify how the objectives are to be achieved.

Formulating good aims and objectives is important because:

They help to focus the study (narrow it down to essentials).

They avoid collection of data that are not strictly necessary for understanding and solving the problem.

They determine the planning of the study and to organise the collection, recording, analysis, interpretation and utilisation of the data.

They are helpful in evaluating the implementation of the study.

TASK 2 – Evaluate aims and objectives

Read the research aim and objectives below around women’s perceptions of ante-natal care (ANC) services. Then answer questions (a) – (c).

Aim: To investigate the perception of women of the ANC services run by the local health authority.

Objectives: 1. To identify a representative group of local women users of ANC clinics.


2. To describe the opinions of this specific group of users about the quality of care at ANC clinics.

3. To share and discuss the results with clinic staff and management.4. To make recommendations to improve the care provided at ANC clinics.

Now answer these questions:

a) Which objectives are concerned with implementation?

b) What clues tell us that the aim and objectives are phrased in operational terms?

c) To what extent are the aim and objectives clear, specific and unambiguous?

FEEDBACKa) The two implementation objectives are:- To share and discuss the results with clinic staff and management (3).- To make recommendations to improve the care provided at ANC clinics

(4).

b) Operational objectives indicate what is to be done or performed and use action words such as to investigate, to identify, to describe, to share and discuss, to make recommendations.

c) The aim and objectives are clear, specific and unambiguous. The only term that might seem vague is “quality of care”, because we do not know which aspects of quality of care the research will focus on. However, this term or key word will be defined and described in detail, as part of the research.

Action WordsOther action words used to state aims and objectives include:

To determine To verifyTo calculate To establishTo measure To listTo compare To map outTo find out

Avoid using vague non-action verbs such as “to appreciate” or “to understand”. Other verbs such as “to study”, “to investigate” or “to find out” can be used, but should only be used to introduce more specific actions in the rest of the sentence.

TASK 3 – Identify aims and objectivesa) The research projects A - C below are all concerned with tuberculosis. Each project has one main aim and several objectives. Identify the aim and the objectives in each set.

b) Having identified the aims, say which aim has all the features of a good aim? Explain your choice.


c) Which of these aims does NOT have the features of a good aim? Explain why they are not good and try rewriting them.

d) Which of these objectives do NOT have the features of a good objective? Explain why they are not good and try rewriting them.

Project A: 1. To understand the TB programme problems from National TB managers.

2. To study the problem of TB in Southern Africa.

3. To map the distribution of patients with TB in Southern Africa.

4. To measure the socio-economic status of TB patients.

Project B:1. To make a list of all the TB clinics and staff in the district.

2. To do a situational analysis of the district TB programme.

3. To make recommendations to the TB services manager.

4. To measure the TB defaulter rate in the district.

Project C:1. To identify a group of TB patients who are below 10 and are currently on treatment.

2. To study the appetite of children with TB.

3. To describe the nutritional status of children with TB.

4. To measure the dietary intake of all children with TB in the study.

FEEDBACKa) Compare your answers to these:

Aim Objectives

Project A:

To study the problem of TB in Southern Africa.

To map the distribution of patients with TB in Southern Africa.

To measure the socio-economic status of TB patients.

To understand the TB programme problems from National TB managers.


Project B:

To do a situational analysis of thedistrict TB programme.

To make a list of all the TB clinics and staff in the district.

To measure the TB defaulter rate in the district.

To make recommendations to the TB services manager.

Project C:

To study the appetite of children with TB.

To identify a group of TB patients who are below 10 and are currently on treatment.

To describe the nutritional status of children with TB.

To measure the dietary intake of all children with TB in the study.

To understand the beliefs of parents about feeding children with TB.

To understand the appetite of children with TB.

b) The third aim, Project C, is the best, because it is clear and precise, worth doing and probably achievable.

c) The first two aims are not very good aims because they are too broad and vague. The first aim in particular is not easily achievable. Both aims use the vague action word “study”.

The two aims could be rewritten like this: To perform a profile of the national distribution and profile of TB

patients. To measure the appetite and diet of children with TB in Cape Town.

d) The only objective that is a little unclear is: To understand the appetite of children with TB.

It would have been better phrased using a more specific action verb instead of “to understand”. This would also make it easier to evaluate whether the objective has been achieved. We could then rewrite the objective as follows: To record or to measure the appetite of children with TB.

In the next section, we explore the development of clear aims and objectives.

4 FORMULATE CLEAR AIMS AND OBJECTIVES

In this section, you will practise formulating clear aims and objectives for research studies.


TASK 4 – Formulate clear aimsLook back at the problem analysis on the high TB defaulter rate presented on page 59 of the reading by Joubert and Ehrlich (2007). Imagine that your literature search and discussions with service managers and nurses have suggested that the key problem has to do with the poor quality of the service. This is noted under “service factors” on the left side of the diagram.

Write down one or two possible aims for a study to look at the influence of the quality of service on TB defaulters.

FEEDBACKPossible study aims include:

To measure the quality of service at different TB clinics and compare it with the defaulter rates at the different clinics

To improve the quality of service given to TB patients and to measure any change in defaulter rate

To measure the level of satisfaction with the quality of service between defaulters and non-defaulters

Now work on your formulation of study objectives.

TASK 5 – Identify clear objectivesThink about this study aim:

To measure the level of satisfaction with the quality of service between defaulters and non-defaulters.

a) What objective would you start with? Write this down.

b) Think about subsequent objectives that need to be achieved so as to reach the main aim. Remember to include at least one implementation objective. Think of the best order in which things should be done. Write down the objectives in this order.

FEEDBACKHere are some objectives that we have come up with:

The first objective might be to find defaulters and non-defaulters:

To identify defaulters and non-defaulters using the same TB service

We then need to measure the level of satisfaction amongst these two groups. So the second objective might be:

To measure the level of satisfaction with the quality of the TB service amongst defaulters and non-defaulters.

After this we need to compare the results between the two groups. So our third objective might be:

To compare the level of satisfaction with the quality of the TB service amongst defaulters and non-defaulters.


TASK 6 – Produce a problem analysis diagram and a problem statement

a) Imagine that you are a hospital manager. You have received complaints from your out-patient staff that they are seeing too many inappropriate cases that should be dealt with at the primary health care clinic. You decide to investigate this further by doing a small research study to look into the matter. Look back at Unit 1 and the way you drew up a problem analysis diagram for the problem of poor use of ANC services. Draw a similar diagram for the possible causes of the inappropriate use of the hospital OPD.

b) Use the diagram to write a problem statement.

FEEDBACKHere is an example of a problem analysis diagram.

b) Possible problem statements might read as follows:

The OPD department at the hospital is very busy. Many of the cases are inappropriate since they could also have been treated at a primary health care clinic. One reason for this could be the access to health services by the local community.

The OPD department at the hospital is very busy. Many of the cases are inappropriate since they could also have been treated at a primary health care clinic. One of the reasons for this could be the poor quality of service that they receive at the primary health care facilities.

The OPD department at the hospital is very busy. Many of the cases are inappropriate since they could also have been treated at a primary health care clinic. One of the reasons could be that they like to be seen by a doctor only at the hospital.

TASK 7 – Formulate possible research aims


Inappropriate OPD cases

Poor access to local PHC clinic

Poor quality of care at local PHC clinic

Preference to see a doctor

Longer waiting times at the PHC clinics

Lack of drugs at PHC clinics

From your discussions and literature review, you have decided to concentrate on access to health services as a possible reason for the inappropriate use of the OPD, as formulated in the problem statement above.

What could be the aim of such a study? Try formulating one or two possible aims.

FEEDBACK

Possible aims of the study could be:

To investigate the difference in access to primary health care clinics and the hospital OPD; or

To investigate the different barriers clients face in attending primary health care clinics; or

To identify whether access to the hospital OPD is a reason why people do not go to the primary health care clinic instead.

TASK 8 – Formulate objectives

Formulate four or five objectives that would enable you to achieve this aim:To investigate the difference in access to primary health care clinics and the hospital OPD.

FEEDBACKHere are some examples of possible study objectives: To measure the number of inappropriate cases seen in the hospital OPD

over a period of one week. To compare the area of residence of inappropriate cases with appropriate

cases. To map out the distribution of primary health care clinics in the district. To compare the total cost for patients in different parts of the district to

come to the hospital or to visit their local clinic. To establish the knowledge of OPD patients about the existence of and

services provided by local primary health care clinics. To compare the time taken to attend the clinic versus the time taken to

attend the hospital OPD. To compare the opening hours of the clinics with those of the OPD.

TASK 9 – Formulate good aims and objectives for your protocola) For the problem statement or question identified for your research, write down

your aim and objectives.

b) Review your aim and objectives by asking yourself these questions: Is the aim:

related to the initial research problem?


clear and precise? defined and achievable?

Are the objectives: dealing with the different aspects of the problem and its contributing factors

in a logical and coherent way? clearly phrased in operational terms, and easy to apply in practice? phrased in a way in which they can be measured? clear, specific and unambiguous? looking at how the research results will be used to solve the problem - in

other words, are they implementation objectives?

6 SESSION SUMMARY

In this session you have further analysed the research question by formulating an appropriate aim and breaking this down into relevant objectives. This is an extremely important step as it now allows you to identify what information you need to collect and to plan how you are going to collect this information.

This study session stressed the importance of having clear and concise aims and objectives. These come from the problem analysis diagram and literature review. Many experienced researchers will tell you that formulating good aims and objectives is the most important part of the research protocol.

In relation to your assignment, you should now be able to develop aims and objectives for your research study. This will allow you to start considering the operationalisation of your research problem. If you wish, you can check your aims and objectives with your lecturer.

Once you have a clear idea of the aims and objectives you can then go on to consider the design of the research and the corresponding research methods. This is addressed in the next two sessions.


Unit 3 – Session 2Introduction to Study DesignsIntroductionOne of the issues that immediately confront researchers in any field is the choice of design for their study. It is very common for researchers to come to this issue with pre-formed ideas reflecting their bias for a particular way of doing research. That is to say, there is already an idea in people's minds about what may be the best data. In an earlier unit we referred to this as brand loyalty. It is very important, however, to remember that the best data is that which can most helpfully answer your research question.

You have already encountered study designs in quantitative research in the Descriptive Epidemiology module. In this session we will briefly review the different study designs and then build on the levels of research problems that were discussed in the first unit, as a way of structuring choice of study design. In this way you will be better able to understand the variety of study designs at your disposal.

Session Contents1 Learning outcomes of this session2 Readings3 Examine study designs4 Strengths and weaknesses of study designs5 Categorising study designs according to the research question6 Session summary

Timing

There are three tasks and two readings in this session; it is a particularly important one in which you will be able to practise analyzing study designs. It should take you about three hours.



By the end of this session, you should be better able to meet the intended learning outcomes in the first column; they are part of or relate to the overall Module Outcome in the second column:

Session Outcomes Module Outcomes Describe the variety of study designs

commonly used in public health research.

Discuss the strengths and weakness of particular designs.

Discuss the choice of study design appropriate to specific research questions.

Justify the selection of particular research designs in relation to the research problem.

Apply different research designs

2 READINGS

Beaglehole, R., Bonita, R. & Kjellstrom, T.(1997). Ch 3 - Types of Study. In Basic Epidemiology. Geneva: WHO Publications: 1 - 26.

Robson, C. (2011). Ch 3 – Developing Your Ideas. In Real World Research: 58 – 62. West Sussex: John Wiley and Sons.

3 EXAMINE STUDY DESIGNS

This session focuses on study designs commonly used in health services research.

Although a bewildering array of study designs is available in health research, study designs can usually be separated into the following categories:- Exploratory- Descriptive - Analytical or Explanatory- Experimental


READINGS

Beaglehole, R., Bonita, R. & Kjellstrom, T. (1997). Ch 3 - Types of Study. In Basic Epidemiology: 1 - 26. Geneva: WHO Publications.

Robson, C. (2011). Ch 3 – Developing Your Ideas. In Real World Research: 58 – 62. West Sussex: John Wiley and Sons.

The readings by Beaglehole et al. (1997) and Robson (2011) provide a succinct overview of each type of study within these categories.

TASK 1 – Formulating study designs

1) Read the articles by Beaglehole et al. (1997) and Robson (2011).

2) Note again that in public health research we are interested in a broad approach to research and would be most interested in ways of collecting a variety of data. With this in mind we will practice formulating study designs within the categories provided in the Beaglehole et al. and Robson readings.

3) Using the example of post-natal depression, for each of the categories - explorative, descriptive, analytical, experimental - describe in the spaces a study design for research in post-natal depression. The first one is done for you.

a. An example of a descriptive study design in post-natal depression employing a variety of data might be:

A study that is interested in the prevalence and characteristics of post-natal depression. This is undertaken through a survey conducted on general practitioners, obstetricians and other health professionals on the number of cases of post-natal depression seen over the past 12 month. As well, in-depth interviews are conducted with women diagnosed of having post-natal depression to gain an insight into the nature of the problems, especially as it is experienced.

An example of an explorative study design in post-natal depression might be:____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

An example of an analytical/explanatory study design in post-natal depression employing a variety of data might be:____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________


An example of an experimental study design in post-natal depression employing a variety of data might be:____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

FEEDBACK

An example of a descriptive study employing a variety of data might be:A study that is interested in the prevalence and characteristics of post-natal depression in your district. A survey is conducted on general practitioners, obstetricians and other health professionals on the number of cases of post-natal depression seen over the past 12 month. As well, in-depth interviews are conducted with women diagnosed of having post-natal depression to gain an insight into the nature of the problems, especially as it is experienced.

An example of an explorative study might be:A study that that is interested in how post-natal depression is experienced by women in the district. A qualitative study is conducted among women who delivered over the past 12 months. In-depth interviews are conducted with women to explore their lived experiences paying a

An example of an analytical study might be:A study that is interested in understanding the relationship between social support and post-natal depression. A survey is conducted on the range of support services available to women during pregnancy and after delivery. This is accompanied by focus group studies with members of a post-natal support group and health service delivery practitioners about social factors, and their experiences with the kinds of support services available.

An example of an experimental study might be:A study that tests the effectiveness of home visits during pregnancy and after delivery in addressing post-natal depression and other health issues. Volunteers for the study are women the first 3 months of pregnancy who are randomly allocated to an intervention group which receives standard care during pregnancy, eg child birth classes, antenatal care plus on-going home visits by mid-wives. A control group receives the standard pregnancy and antenatal care. Survey data is collected from both groups on quality of social support, psychological well being and socio-economic characteristics before and after the birth of the child. In-depth interviews are conducted with selected individuals from intervention and control groups which focus on quality of social support.

As you can see there are differences in research study design which are appropriate to different uses. As the next section indicates, however, each study design has strengths and weakness.


4 STRENGTHS AND WEAKNESSES OF STUDY DESIGNS

It is very important to appreciate that the choice of study design must take a number of factors into account.

TASK 2 – Critique study designsRe-read the article the reading by Beaglehole et al. (1997), and critique the study designs above on post-natal depression, especially in terms of strengths and weaknesses. Use the chart below to indicate what you think are the strengths and weaknesses in each of the study designs for antenatal depression. Think about how you would correct some the weaknesses.

Study design for antenatal depression

Strengths Weaknesses

Descriptive study

Explorative study

Analytical study

Experimental study


FEEDBACK

See the feedback on the following page.Study design for antenatal depression

Strengths Weaknesses

Descriptive study Will establish the size and distribution of the problem and should be relatively easy to do within a short space of time and will be relatively inexpensive

Difficult to identify causal risk factors which could assist in designing an intervention

Exploratory study Will provide an in-depth information about the relational dynamics and context within this specific setting that led to women developing post-natal depression. It will provide ideas for intervention and treatment that are context-sensitive.

Difficult to determine whether the factors are

Analytical study

Allows the identification of associated risk factors for depression during pregnancy

Will not evaluate the effectiveness of any interventions which have been formulated

Experimental study Will allow us to evaluate any interventions

Can be expensive and difficult to organise.

What we want to demonstrate is that there are a variety of study designs which help to assist in painting a fuller picture of the problem under examination. However, consistent with our earlier discussion on level of research question, we would also want to make sure that our study design is in the first place pitched at the appropriate level. It is to this that we now turn.


5 CATEGORISING STUDY DESIGNS ACCORDING TO THE RESEARCH QUESTION

Having examined the range of study designs in health systems research we are now in a position to start carefully choosing designs for specific research purposes. The next few activities will provide you with the knowledge and skills to select appropriate study designs to your research needs.

In Units 1 and 2 we examined levels of complexity for research problems and summarised these as:1) Problems that seek to describe or explore a phenomenon or an event. 2) Problems that look at whether there are relationships between phenomena, i.e. try to explain a phenomenon. 3) Problems that seek to generate information about the relationships.We are now in a position to use this categorisation to assist us in choosing a study design. The table below, taken from Varkevisser et al. (1997), reflects the categories above, i.e. (1) gaining knowledge about the characteristics of the problem, (2) establishing the relationships between various factors or (3) discovering the extent to which particular factors cause the problems and assessing interventions that would prevent, control or solve the problems. The table outlines the types of study design best suited to each category.

State of knowledge of the problem

Type of researchquestion

Type of study design

Knowing that a problem exists, but knowing little about its characteristics or possible causes (level 1 question)

What is the nature/magnitude of the problem?

Who is affected?

How do the affected people behave?

What do they know, believe and think about the problem?

Exploratory or descriptive studies, such as:

Descriptive case studies

Exploratory or Descriptive Qualitative studies

Descriptive Cross sectional surveys

Suspecting that certain factors contribute to the problem(level 2 question)

Are certain factors indeed associated with the problem?(e.g. lack of preschool education related to low school performance? Is low fibre diet related to carcinoma of the large intestine?)

Analytical (comparative studies) such as:

- Analytical Cross-sectional studies

- Case control studies- Cohort studies- Theoretically driven

qualitative studies

Having established that certain factors are associated with the

What is the cause of the problem?

Cohort studies


problem, desiring to establish the extent to which a particular factor causes or contributes to the problem (level 2 question)

Will the removal of a particular factor prevent or reduce the problem? (e.g. stopping smoking, providing safe water)

Experimental or quasi-experimental study designs

Having sufficient knowledge about the cause to develop and assess an intervention that would prevent, control or solve the problem

(level 3 question)

What is the effect of a particular intervention /strategy?(e.g. being treated with a certain drug, being exposed to a certain type of health education)

Which of the two alternative strategies gives better results?

Are the results in proportion to time/money spent?


Evaluation studies


Type of researchquestion


Having sufficient knowledge about the cause to develop and assess an intervention that would prevent, control or solve the problem

(level 3 question)

What is the effect of a particular intervention/strategy?

(e.g. being treated with a certain drug, being exposed to a certain type of health education)

Which of the two alternative strategies gives better results?

Are the results in proportion to time/money spent?


Evaluation studies

TASK 3 – Practise categorizing study designs

Fill in the columns below selecting the appropriate study designs for the following problems involving teenage pregnancy.

1) The influence of a new school curriculum and classroom educational activities on student knowledge and attitudes to teenage pregnancy

2) Factors associated with the prevalence of pregnancy in teenagers3) The frequency of pregnancy in teenagers.



Type of research question


1)

2)

3)

FEEDBACK

Your chart should look something like the one below:


Type of research question


1) Having sufficient knowledge about the cause to develop and assess an intervention that would prevent, control or solve the problem (level 3 question)

What is the effect of one particular set of educational activities compared to another?

What are the cost and resource implications of each activity?

Experimental or quasi-experimental studydesign** see below

2) Suspecting that certain factors contribute to the problem (level 2 question)

What are the socio-economic characteristics of the teenagers who are most likely to become pregnant?

Analytical study such as a Case control study design

This may include a study which compared the family and social experiences of women who had teenage pregnancies with a group who did not.

3) Knowing that a problem What is the Descriptive study design


exists, but knowing little about its characteristics or possible causes (level 1 question)

nature/magnitude of teenage pregnancy?

such as a cross sectional survey one design may be to examine the birth records oflocal delivery centresexamining the number andnature of delivery to women 16 years and under.

** For example, an appropriate design may be an in-depth, on-going observational study on classroom activities which examined the ways in which sex education and related topics were handled in and were received by students two school. One school has introduced a problem-based sex education curriculum, another continues to use the traditional version, we can attempt to measure the uptake of each by students. Accompanied to this might be an analysis of curriculum material (policy documents, subject materials etc), related to sex education.

It may be that your descriptions differ from those given above. That does not matter. The most important thing is that you begin to understand the ways in which we can increase or decrease the breadth of the research enterprise. All of the above examples are useful areas to research. We should however remember that public health research in particular is interested to ensure that research goes beyond the purely descriptive level in order to put this kind of knowledge into action/intervention to change.

6 SESSION SUMMARY

In this session we have looked at ways in which your study design can be given depth, by making sure that questions are asked at the appropriate level of complexity. In the next two sessions of this unit we will look at data collection methods.


Unit 3 – Session 3Research Methods in Public Health ResearchIntroduction

The aim of this study session is to further develop knowledge of study designs and methods for conducting public health research.

Contents1 Learning outcomes of this session2 Readings3 Overview of fixed and flexible design strategies4 Key Considerations for Fixed Design Quantitative Studies 5 The Purpose of Qualitative Health Research6 Methodological Considerations for Qualitative Studies7 Session summary

TimingThere are five tasks and three readings in this session; it is mainly focused on ensuring that you have a good understanding of quantitative data collection techniques and terminology. The timing of it depends on your prior knowledge of these concepts.


By the end of this session, you should be better able to meet the intended learning outcomes in the first column; they are part of or relate to the overall Module Outcome in the second column:

Session Outcomes Module Outcomes Distinguish between quantitative and

qualitative study designs Identify the main design issues for

quantitative studies. Describe the purpose of qualitative

research in public health research. Understand the methodological

considerations for collecting qualitative data.

Apply different research designs

Explore the application of qualitative and quantitative approaches to the problem


Assignment reminder

By the end of the study session, you should have chosen an appropriate study design for your proposed research by revisiting your research question and considering the strengths and weaknesses of using a fixed or flexible design strategy. This decision should be based on a preliminary consideration of the nature or type of data that you will collect and from where you will obtain the data.

2 READINGS

Kellehear, A. (1993). Ch 9 - Rethinking the Survey. In Colquhoun, D. & Kellehear, D. Health Research in Practice: 126 - 137. London: Chapman & Hall.

Robson, C. (2011). Ch 4 – General Design Issues. In Real World Research: 70 – 80. West Sussex: John Wiley and Sons.

Robson, C. (2011). Ch 5 – Fixed Designs. In Real World Research: 81 – 93. West Sussex: John Wiley and Sons.

Pope, C. Ziebland, S. & Mays, N.(2000). Analysing Qualitative Data. British Medical Journal, 320:114 - 116. [Online], Available: http://www.bmj.com/cgi/content/full/320/7228/114 [9/19/2000 11:47 AM]

Rice, P. R. & Ezzy, D. (1999). Sampling Strategies for Qualitative Research. In Qualitative Research Methods - A Health Focus. Sydney: Oxford University Press: 40 - 50.

3 OVERVIEW OF FIXED AND FLEXIBLE DESIGN STRATEGIES

This session builds on the earlier one in which you developed aims and objectives.

TASK 1 – Distinguish between fixed and flexible study designs

1) Read the chapter by Robson (2011).

2) Robson distinguishes between fixed, flexible and what he calls multi-strategy design strategies. He equates the fixed design with a quantitative study, and the


http://www.bmj.com/cgi/content/full/320/7228/114

flexible design with a qualitative study. Why do you think is he making this deduction? Do you agree with him?

FEEDBACK

Quantitative studies always involve collecting information (numerical data) on variables that have been pre-specified. We then have a list of information elements (variables) that we want to count or describe numerically. To make sure that we can compare subjects, the variables must be counted or described numerically in exactly the same way – otherwise the comparison is not valid.

Qualitative studies on the other hand, involve collecting information in the form of words. Since people are unique, they may express similar issues in different ways and using different words. Thus in data collection, through interviews, for example, the way that we collect data cannot be pre-specified, although we have an idea of the main questions that we want to ask to each participant -hence the notion that qualitative studies are flexible by design. Of course, this flexibility does not only pertain to data collection. (Note: This issue will be covered in detail in the Qualitative Research Methods module.)

However, qualitative studies can be ‘fixed’, as is commonly observed in market research and evaluations. In these instances, data collection takes place through focus group discussions and focused interviews which contain fixed open-ended questions that we want to get information (responses) about.

4 KEY CONSIDERATIONS FOR QUANTITATIVE STUDIES

In the Descriptive Epidemiology module you have dealt extensively with the characteristics of quantitative research. It would be a good idea to skim through that module and refresh your understanding. In this section, we will consider key issues that may influence the choice for undertaking a fixed design quantitative study.

READINGSRobson, C. (2011). Ch 5 – Fixed Designs. In Real World Research: 81 – 93. West Sussex: John Wiley and Sons.

Kellehear, A. (1993). Ch 9 - Rethinking the Survey. In Colquhoun, D. & Kellehear, D. Health Research in Practice: 126 - 137. London: Chapman & Hall.


TASK 2 – Considerations for using a fixed design quantitative study

1. Read Robson (2011) and Kellehear (1993).

2. What are some key issues that these authors highlight when considering a fixed design, quantitative study?

FEEDBACK

Robson points out the following key features of fixed designs:a) Fixed designs are theory-driven. This implies that a clear and known

conceptual framework should exist within which fixed designs can be implemented. Conversely, without a known conceptual framework, a quantitative study does not have grounding or validity; instead an alternative design strategy should be considered.

b) Quantitative studies are concerned with group properties and general tendencies. Thus they require rather large samples. Also, they are not able to capture the complexities of human behavior.

c) Requires objectivity of the research instrument for validity. Various criteria for validity of measurements need to be adhered to when conducting quantitative studies. These measures need to be good proxies for the variables that they represent.

Kellehear argues that the decision of the study design should go beyond brand loyalty to consider the “people under investigation”.d) Characteristics of the target population. In certain instances, where

shortened, less intensive and even invasive interactions with the study subjects are desirable, fixed design studies may be preferred.

TASK 3 – Your assignmentConsider the four features of quantitative research mentioned above, and make an argument for or against using a fixed design strategy for your proposed study.

5 THE PURPOSE OF QUALITATIVE STUDIES

We have to some extent discussed with the nature and purpose of qualitative research methods in earlier units. It is very important to make sure we have a full grasp of the significance of using qualitative research methods in order to do justice to our notion of public health research. It is simply not enough to say, as some authors have put it, that “qualitative research methods are purely exploratory”. This does not serve our purpose well at all. It is true that qualitative research does tend to be used to uncover values, beliefs and experiences that might otherwise be inaccessible in other ways of investigating. However, qualitative research can also be confirmatory in that it


can demonstrate the causes of certain findings from surveys. These and other uses of qualitative research methods are discussed in the following article.

READINGPope, C. Ziebland, S. & Mays, N. (2000). Analysing Qualitative Data. British Medical Journal, 320:114 - 116. [Online], Available: http://www.bmj.com/cgi/content/full/320/7228/114 [9/19/2000 11:47 AM].

TASK 1 – Discuss the value of qualitative research for health research

Read the article by Pope, Ziebland and Mays (2000). In this paper Pope and Mays make a claim about the importance of qualitative methods for health research. Discuss this claim in relation to our earlier discussion about the nature of health systems research.

FEEDBACK

If you noted that the action and problem-centred nature of public health research requires that it be driven by the real issue rather than a researcher’s theoretical standpoint, you have done well. You may also have discussed the importance for health research of combining the so-called strengths of each (given in Box 2 of the article). Having explained the purpose of qualitative research, we are now in a better position to explore the different methods of collecting qualitative data.

6 COMMON METHODS OF COLLECTING QUALITATIVE DATA

There are three main methods of collecting qualitative data: Individual interviews Focus Group Discussions

At this stage you will be briefly introduced to each method. In the next session we will explore each method in more detail.

6.1 Individual Interviews

It would be fair to say that interviews form by far the most common method of data collection in qualitative research. This is usually described as ‘in-depth’ interviewing since the aim is to gather information which has a number of characteristics.


http://www.bmj.com/cgi/content/full/320/7228/114

Firstly it is from the perspective of the respondent, not the researcher. It is true that by nature in-depth interviews are driven to some extent by the researcher. However, rather than lead the respondents through a series of prepared questions, as far as possible, the researcher attempts to elicit the respondents meaning and depth of coverage. Secondly, prompts and probes (“Why do you think that is?” “Can you tell me more about that?”) are used to get below the initial responses. Lastly, the management of the interview is such that researchers often actively pursue unanticipated issues that emerge.

6.2 Focus Group Discussions

There are a number of reasons for organising focus group discussions for qualitative research. They range from seeking consensus on a particular issue to exploring a diversity of views available. They all attempt to use a social basis for information gathering, in other words they exploit the dynamics that are involved when a group of people discuss a particular issue. Focus group discussions are often justified on the grounds that more ideas are collected when people are able to ‘bounce ideas’ off each other, in other words there is something to be gained from the synergy involved in groups.

However, this may not always be the case. Morgan quotes a study (Annual Review of Sociology, 22: 129 - 224) in which it was found that collecting information from groups generated only 60-70% of the ideas that were gained from interviewing the equivalent number of individuals. Of course, the time involved in interviewing individuals is far greater than that required when conducting focus groups and this is considered to be a distinct advantage in favour of focus group discussions.

7 SAMPLING IN QUALITATIVE RESEARCH

In an earlier session, you examined some of the issues related to sampling for surveys, however there are a number of sampling questions that relate to qualitative research which need to be addressed.

READING

Rice, P. R. & Ezzy, D. (1999). Sampling Strategies for Qualitative Research. In Qualitative Research Methods - A Health Focus. Sydney: Oxford University Press: 40 - 50.

TASK 4 – Clarify key concepts in qualitative sampling

Read the above chapter by Rice and Ezzy, and then answer the questions below.


This article makes the point that sampling in qualitative research is not meant to be generalisable in a statistical sense, but is instead meant to be purposive.

What do the authors mean by purposive?___________________________________________________________________________________________________________________________________________________________________________________________________

Why are information rich cases especially useful in qualitative research?___________________________________________________________________________________________________________________________________________________________________________________________________

Sometimes the researchers deliberately try to recruit deviant or extreme cases in their sample. Why is this?___________________________________________________________________________________________________________________________________________________________________________________________________

What do qualitative researchers mean by the term “saturation”?___________________________________________________________________________________________________________________________________________________________________________________________________

FEEDBACK

Unlike quantitative research, qualitative researchers are usually more interested in the nature or processes in a phenomenon or an experience rather than its distribution. It makes sense therefore to deliberately or purposively recruit participants who have some exposure to the phenomenon under study. Similarly, those cases that have more exposure to the experience – information-rich cases - are likely to be more useful informants. The use of extreme or deviant cases is a useful way of throwing light on more typical cases or of challenging ideas. Sometimes this is called negative case sampling and this will be dealt with in a future session concerned with strengthening rigour in qualitative research. Saturation is the term given to the point in qualitative research when future sampling does not seem to be offering any new insights into the phenomenon under investigation.

6 SESSION SUMMARY

This session was designed to introduce you to a different way of thinking about quantitative and qualitative research approaches by denoting them as


fixed and flexible designs. You were familiarized with key considerations when making a decision for fixed design quantitative studies, to complement the knowledge you gained from Descriptive Epidemiology module. This session included an overview of the purpose and the methods involved in qualitative research.


CONCLUSION OF UNIT 3

This unit has attempted to provide you with an overview of the different study designs used in public health research and the common methods of collecting qualitative data.

One striking difference between quantitative and qualitative methods is the relationship between data collection and analysis. In quantitative methods it is usually the case that all data is collected before analysis begins. In qualitative methods however, data collection and analysis often take place side-by-side. This is because qualitative methods often seek to revise hunches and propositions along the way. Indeed as we have said, purposive sampling requires that respondents be recruited to provide cases of rich-information. The kinds of information of interest to the researcher often change as the research progresses, and in light of the on-going analysis.

Assignment reminder

You should now be in a position to operationalize your research question, by developing aims and objectives, and considering an appropriate study design based on the type of data that you wish to collect and the target population. You are welcome to submit this design to your supervisor/lecturer for feedback.


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